Volume 117, Number 4, February 2017
|Number of page(s)||7|
|Section||Geophysics, Astronomy and Astrophysics|
|Published online||03 April 2017|
Study of MRI in stratified viscous plasma configuration
1 ENEA, Fusion and Nuclear Safety Department, C.R. Frascati - Via E. Fermi, 45 (00044) Frascati (Roma), Italy
2 L.T. Calcoli - Via Bergamo, 60 (23807) Merate (LC), Italy
3 Department of Physics, “Sapienza” University of Rome - P.le Aldo Moro, 5 (00185) Roma, Italy
Received: 5 August 2016
Accepted: 13 March 2017
We analyze the morphology of the magneto-rotational instability (MRI) for a stratified viscous plasma disk configuration in differential rotation, taking into account the so-called corotation theorem for the background profile. In order to select the intrinsic Alfvénic nature of MRI, we deal with an incompressible plasma and we adopt a formulation of the local perturbation analysis based on the use of the magnetic flux function as a dynamical variable. Our study outlines, as consequence of the corotation condition, a marked asymmetry of the MRI with respect to the equatorial plane, particularly evident in a complete damping of the instability over a positive critical height on the equatorial plane. We also emphasize how such a feature is already present (although less pronounced) even in the ideal case, restoring a dependence of the MRI on the stratified morphology of the gravitational field.
PACS: 97.10.Gz – Accretion and accretion disks / 96.25.St – Plasma and MHD instabilities / 98.35.Eg – Electric and magnetic fields
© EPLA, 2017
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.